Hummer 2007 H2 Owner's Manual page 199

Automatic Operation
AUTO (Automatic): When automatic operation is
active the system will control the inside
temperature, the air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will
change to show the current driver's set
temperature, delivery mode and fan speed.
Press the AUTO button again within
five seconds to display the passenger's set
temperature.
If the driver and passenger's temperature
settings are not the same, the opposite side
temperature setting will be displayed for
an additional five seconds. To make the
passenger's temperature the same as
the driver's press and hold the AUTO button
for about four seconds.
When auto is selected, the air conditioning
operation and air inlet will be automatically
controlled. The air conditioning compressor will
run when the outside temperature is over about
40°F (4°C). The air inlet will normally be set to
outside air. If it's hot outside, the air inlet may
automatically switch to recirculate inside air to
help quickly cool down your vehicle. The light
on the button will illuminate in recirculation.
2. Set the driver's and passenger's temperature.
To find your comfort setting, start with a 74°F
(23°C) temperature setting and allow about
20 minutes for the system to regulate. Turn the
driver's or passenger's side temperature knob
to adjust the temperature setting as necessary.
If you choose the temperature setting of 60°F
(15°C) the system will remain at the maximum
cooling setting. If you choose the temperature
setting of 90°F (32°C) the system will remain at
the maximum heat setting. Choosing either
maximum setting will not cause the vehicle to
heat or cool any faster.
Be careful not to cover the sensor located on
the top of the instrument panel near the
windshield. This sensor regulates air
temperature based on sun load, and also
turns on your headlamps.
To avoid blowing cold air in cold weather, the
system will delay turning on the fan until
warm air is available. The length of delay
depends on the engine coolant temperature.
Pressing the fan switch will override this delay
and change the fan to a selected speed.
199